git-merge-octopus.sh

   1 #!/bin/sh
   2 #
   3 # Copyright (c) 2005 Junio C Hamano
   4 #
   5 # Resolve two or more trees.
   6 #
   7
   8 . git-sh-setup
   9
  10 LF='
  11 '
  12
  13 # The first parameters up to -- are merge bases; the rest are heads.
  14 bases= head= remotes= sep_seen=
  15 for arg
  16 do
  17         case ",$sep_seen,$head,$arg," in
  18         *,--,)
  19                 sep_seen=yes
  20                 ;;
  21         ,yes,,*)
  22                 head=$arg
  23                 ;;
  24         ,yes,*)
  25                 remotes="$remotes$arg "
  26                 ;;
  27         *)
  28                 bases="$bases$arg "
  29                 ;;
  30         esac
  31 done
  32
  33 # Reject if this is not an octopus -- resolve should be used instead.
  34 case "$remotes" in
  35 ?*' '?*)
  36         ;;
  37 *)
  38         exit 2 ;;
  39 esac
  40
  41 # MRC is the current "merge reference commit"
  42 # MRT is the current "merge result tree"
  43
  44 if ! git diff-index --quiet --cached HEAD --
  45 then
  46     gettextln "Error: Your local changes to the following files would be overwritten by merge"
  47     git diff-index --cached --name-only HEAD -- | sed -e 's/^/    /'
  48     exit 2
  49 fi
  50 MRC=$(git rev-parse --verify -q $head)
  51 MRT=$(git write-tree)
  52 NON_FF_MERGE=0
  53 OCTOPUS_FAILURE=0
  54 for SHA1 in $remotes
  55 do
  56         case "$OCTOPUS_FAILURE" in
  57         1)
  58                 # We allow only last one to have a hand-resolvable
  59                 # conflicts.  Last round failed and we still had
  60                 # a head to merge.
  61                 gettextln "Automated merge did not work."
  62                 gettextln "Should not be doing an octopus."
  63                 exit 2
  64         esac
  65
  66         eval pretty_name=\${GITHEAD_$SHA1:-$SHA1}
  67         if test "$SHA1" = "$pretty_name"
  68         then
  69                 SHA1_UP="$(echo "$SHA1" | tr a-z A-Z)"
  70                 eval pretty_name=\${GITHEAD_$SHA1_UP:-$pretty_name}
  71         fi
  72         common=$(git merge-base --all $SHA1 $MRC) ||
  73                 die "$(eval_gettext "Unable to find common commit with \$pretty_name")"
  74
  75         case "$LF$common$LF" in
  76         *"$LF$SHA1$LF"*)
  77                 eval_gettextln "Already up to date with \$pretty_name"
  78                 continue
  79                 ;;
  80         esac
  81
  82         if test "$common,$NON_FF_MERGE" = "$MRC,0"
  83         then
  84                 # The first head being merged was a fast-forward.
  85                 # Advance MRC to the head being merged, and use that
  86                 # tree as the intermediate result of the merge.
  87                 # We still need to count this as part of the parent set.
  88
  89                 eval_gettextln "Fast-forwarding to: \$pretty_name"
  90                 git read-tree -u -m $head $SHA1 || exit
  91                 MRC=$SHA1 MRT=$(git write-tree)
  92                 continue
  93         fi
  94
  95         NON_FF_MERGE=1
  96
  97         eval_gettextln "Trying simple merge with \$pretty_name"
  98         git read-tree -u -m --aggressive  $common $MRT $SHA1 || exit 2
  99         next=$(git write-tree 2>/dev/null)
 100         if test $? -ne 0
 101         then
 102                 gettextln "Simple merge did not work, trying automatic merge."
 103                 git merge-index -o git-merge-one-file -a ||
 104                 OCTOPUS_FAILURE=1
 105                 next=$(git write-tree 2>/dev/null)
 106         fi
 107
 108         MRC="$MRC $SHA1"
 109         MRT=$next
 110 done
 111
 112 exit "$OCTOPUS_FAILURE"